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// Copyright (c) 2012, Suryandaru Triandana <syndtr@gmail.com>
// All rights reserved.
//
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
package util
import ( "encoding/binary" )
// Hash return hash of the given data.
func Hash(data []byte, seed uint32) uint32 { // Similar to murmur hash
const ( m = uint32(0xc6a4a793) r = uint32(24) ) var ( h = seed ^ (uint32(len(data)) * m) i int )
for n := len(data) - len(data)%4; i < n; i += 4 { h += binary.LittleEndian.Uint32(data[i:]) h *= m h ^= (h >> 16) }
switch len(data) - i { default: panic("not reached") case 3: h += uint32(data[i+2]) << 16 fallthrough case 2: h += uint32(data[i+1]) << 8 fallthrough case 1: h += uint32(data[i]) h *= m h ^= (h >> r) case 0: }
return h }
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